Device for initial colling of filament on filament core

ABSTRACT

The present invention relates to electric engineering, in particular, to manufacturing incandescent elements and, more precisely, to a device for initial coiling of a filament on a filament core. The essence of the invention resides in that in a device for initial coiling of a thin wire filament on a filament core comprising a base, a spool with said thin wire, a hollow spindle cantilever-mounted on said base so as to be rotatable thereon, with its free end carrying said spool and a nozzle housed in the spool near its end face, said nozzle being intended to let the core, pulled through the hollow spindle, pass therethrough, a housing disposed coaxially with said spool and mounted on said base, a fixing means is provided for securing the position of a portion of the thin wire, fed to the core for coiling, at a predetermined angle, said fixing means being fastened inside the housing on the bottom thereof, and the housing itself being so mounted on the base as to enable it to move longitudinally relative to the spool. The proposed device is preferably used in manufacturing incandescent lamps.

United States Patent 1191 Konin et al.

[ Nov. 4, 1975 DEVICE FOR INITIAL COLLING 0F FILAMENT 0N FILAMENT CORE [76] Inventors: Mikhail Alexeevish Konin, prospekt 50 let Oktyabrya, 24, kv. 46; Anatoly Ilich Alexeikin, prospekt 50 let Oktyabrya, 15, kv. 69; Petr Ivanovich Nikolaev, ulitsa Popova, 62, kv. 61; Viktor Fedorovich Kazakov, ulitsa Volodarskogo, 80, kv. 5; Nikolai Stepanovich Alshin, ulitsa Svetotekhniki, l7, kv. 3, all of Saransk, U.S.S.R.

22 Filed: May2, 1974 21 Appl. No.: 466,254

FOREIGN PATENTS 0R APPLICATIONS 458,604 8/1949 Canada 57/18 Primary ExaminerLowell A. Larson Attorney, Agent, or FirmHaseltine, Lake & Waters [57] ABSTRACT The present invention relates to electric engineering, in particular, to manufacturing incandescent elements and, more precisely, to a device for initial coiling of a filament on a filament core.

The essence of the invention resides in that in a device for initial coiling of a thin wire filament on a filament core comprising a base, a spool with said thin wire, a hollow spindle cantilever-mounted on said base so as to be rotatable thereon, with its free end carrying said spool and a nozzle housed in the spool near its end face, said nozzle being intended to let the core, pulled through the hollow spindle, pass therethrough, a housing disposed coaxially with said spool and mounted on said base, a fixing means is provided for securing the position of a portion of the thin wire, fed to the core for coiling, at a predetermined angle, said fixing means being fastened inside the housing on the bottom thereof, and the housing itself being so mounted on the base as to enable it to move longitudinally relative to the spool.

The proposed device is preferably used in manufacturing incandescent lamps.

3 Claims, 2 Drawing Figures U.S. Patent Nov. 4, 1975 Sheet2of2 3,916,959

DEVICE FOR INITIAL COLLING OF FILAMENT ON FILAMENT CORE The present invention relates to electrical engineering, in particular, to the manufacture of incandescent elements and, more precisely, to a device for initial coiling of a filament on a filament core.

A device for initial coiling of a filament on a filament core is known, which comprises a tungsten wire-carrying spool rigidly fastened on a hollow spindle and a housing enclosing said spool. The housing is intended to confine the size of a loop formed of the wire to be coiled under centrifugal forces appearing during the rotation of the spool. The centrifugal forces cause formation of the loop and ensure its tension necessary for performing the coiling process.

However, unstable tensioning of the tungsten wire at the point of its unrolling from the spool (catching between the turns, contacting of the spool side pieces, etc.) results in a variation of the shape and position of said loop, confined between said housing and the core, relative to the nozzle, disturbing therewith the pitch of the coil. Furthermore, said device does not provide for the use of elements enabling both the heating of the tungsten wire to be coiled by directly passing current through it, and registering a break thereof.

It is an object of the present invention to improve the above device for initial coiling of a filament on the filament core with a view to increasing its reliability and providing for uniform winding of the wire on the filament core with a preset coil pitch.

The present invention is, in essence, aimed at providing a device for initial coiling of a filament made of thin wire on a filament core, which would ensure stable tensioning of a wire portion being applied to the core and fixation of a loop formed of the wire under the action of centrifugal forces, preserving thereby a predetermined shape and position of the loop relative to the nozzle.

This object is achieved by that in a device for initial coiling of a thin wire filament on the filament core comprising a base, a spool with said thin wire, a freely rotated hollow spindle cantilever-mounted on the base, with its free end carrying said spool, a nozzle inserted into said free end from its end-face, said nozzle being adapted to let the core, pulled through the hollow spin dle in the process of filament coiling, pass there through, and a housing arranged concentrically with the spool and mounted on the base, according to the invention, a fixing means is provided, securing at a given angle the position of a thin wire portion fed for coiling to the core, said fixing means being fastened inside the housing to the bottom thereof and the housing itself being so secured on the base as to be allowed to move longitudinally relative to the spool.

It is advisable that the fixing means in the device for initial coiling of a thin wire filament on the filament core should be made of conductive material in the form of a ring arranged in a plane normal to and coaxially with the hollow spindle axis and in constant direct contact with the thin wire being coiled, forming thereby a slide contact connecting a portion of the thin coiled wire fed to the core into an electric circuit for heating by electric current said thin wire portion and controlling its continuity.

For controlling breakage of said thin wire, the device for initial coiling of a thin wire filament on the filament core should preferably be provided with a relay con- 2 nected into the electric circuit in series with a portion of the thin wire being coiled.

The proposed device for initial coiling of a thin wire filament on the filament core is highly efficient (25,000 turns per minute), reliable in operation, easy in manufacture and servicing. Owing to the fixing means built into the device it is possible to set a portion of the wire being fed to the core at a given angle and to directly heat said portion by electric current, thereby allowing for the use of a wide variety of wire gauges.

Design features of a specific embodiment of the device according to the invention are described below with reference to the accompanying drawings, wherein:

FIG. 1 is a longitudinal section of a device for initial filament coiling, according to the invention; and

FIG. 2 is a functional diagram of the device according to the invention.

Referring now to FIG. 1, the device for initial coiling of a filament made of thin wire on the filament core comprises a base I, a spool 2 with a thin tungsten wire 3 wound thereon, a hollow spindle 4 cantilevermounted in two radial thrust bearings 5 disposed in the base 1. The spool 2 is fixed on a free end 6 of the hollow spindle 4 by means of a rubber ring 7 of a rectangular cross-section. Inserted into a tapered hole 8 on the endface of the hollow-spindle free end is a draw-in chuck with a nozzle 10. A housing II arranged coaxially with the spool 2 is fastened in a holder 12 which, in turn, is secured on rods 13 movably fitted into bushings 14.

The bushings 14 are rigidly fixed on the base I and serve as guides for the rods 13. Screwed onto threaded free ends 15 of the rods 13 are nuts 16 by means of which the rods 13 and hence the housing II can be shifted along the spindle 4. Each rod has a spring 17 confined between the bushing 14 and holder 12. The

nuts 16 and springs 17 serve for adjusting the housing II in a required position. The housing II is provided with a fixing means 18 assuring the position of a portion 19 of the thin wire being coiled, which is fed to the core at a preset angle. Besides, the device has a take-up reel 20, a feed reel 21 and a unit 22 for heating by electric current the thin wire being coiled. Wound on the feed reel 21 is a core 23. The take-up reel 20 receives the coiled filament.

The coiled-wire heating unit 22 comprises a series circuit including a current regulator 24, a relay 25 for controlling breakage of the wire being coiled, the portion 19 of the wire being coiled and a pilot lamp 26.

A drive including an electric motor (not shown) serves to set the device in motion through a flat driving belt 27 stretched over a pulley/28 connected with the hollow spindle 4, a worm pair 29 consisting of a worm 30 anda worm gear 31, a driving shaft 32 mechanically connected through a toothed gearing 33 made up of two helical gears 34 and 35 with the worm wheel 31 and transmitting movementboth to a pulling disk 36 through a worm pair 37 consisting of a worm 38 and a worm gear 39 and to a take-up reel 20 through a worm pair 40 made up of a worm 41 and a worm gear 42. The required pull-up of the core is ensured by appropriately turning the feed reel 21 and take-up reel 20 (reel 21, in the direction of the arrow and reel 20, conunter the arrow, as shown in FIG. 2). The pulling disk 36 and an idler 43, encircled together by a number of loops of the core having the tungsten wire coiled thereon serve for adjusting a required pitch of the wound coil.

The feed reel 21 is provided with a brake (not shown).

The take-up reel 20 and an axle 44 are coupled through a friction clutch (not shown).

The spool 2 is made in the form ofa bush 45 with two side pieces 46 and 47. An outer face of the side piece 47 is convex. The fixing means 18 is made of conductive material, for example brass, in the form of a ring disposed in a plane normal to the hollow spindle 4 axis and coaxially therewith. The fixing ring is in constant direct contact with the thin wire being coiled, forming thereby an electric slide contact 48 and hence a closed circuit wherein the current flows through the coiled wire portion 19 and heats it.

The above-described device operates in the following manner. Prior to starting the device it is necessary to fit the feed reel 21 with the core 23 and the take-up reel 20 on their appropriate axles and spool 2 with the tungsten wire 3, on the free end of the hollow spindle 4. The pulling disk of a required diameter corresponding to a given pitch of coiling of the tungsten wire 3 on the core 23 is also mounted on its axle. The core 23 is then passed through the hollow spindle 4 and nozzle and wound in several loops on the pulling disk 36 and idler 43, whereupon the core end is fixed to the take-up reel 20. The subsequent pull-up adjustment of the core 23 prior to its entry into the hollow spindle 4 and before its winding on reel is accomplished by appropriately turning the feed reel 21 and take-up reel 20. The degree of core tension is measured by a dynamometer (not shown).

It is further required to fasten the tungsten wire 3. For this purpose it is necessary to shift the housing II to the left, bring out the tungsten wire end from the spool and wind several turns of the wire on the core 23 by manually turning the hollow spindle 4 by 2-3 revolutions, in the direction shown with the arrow preforming therewith a loop with the help of the convex face of the spool side piece 27. Such a formation of the loop prevents the occurrence of a loop whip and thereby possible break of the tungsten wire and core when starting the device. After completing the above procedure, housing [I is replaced in its original position and the device is set going by switching on the electric motor (not shown).

With the device operating, the centrifugal forces elongate the preformed loop till it touches the housing (as is shown in FIG. 1) and hence tension the portion 19 of the tungsten wire, this being essential for the normal coiling process. By turning the nut 16, it is possible to adjust the position of housing II, shifting it so far as to place the tungsten wire portion 19 at a predetermined angle relative to the hollow spindle axis. This angle depends on the elastic properties of the tungsten wire 3 wound on the spool and can be adjustable in the range of from 60 to 80. The current regulator 24 is used to set a required value of the current flowing through the tungsten wire portion 19 for heating it to a temperature of 600-800C. Temperatures are assessed visually by temper colours. On completion of the above the device for initial filament coiling continues operat- Should a break of the tungsten wire occur, the relay 25 will be de-energized, its closing contact 25 will close and switch on the pilot lamp 26. The device can 4 be cut off either manually by the operator or automatically by providing the relay 25 with a breakdown signal contact (not shown).

The proposed device for initial coiling of a thin wire on the core, embodied as described above, has undergone performance tests. The coiling process has been successfully carried out with the tungsten wire ranging in diameter from 20 to 120 microns and the core, from to 500 microns at a rate of 18,00025,000 turns per minute.

The pitch error of the tungsten wire coiled on the core did not exceed 10 per cent of the wire diameter. The fixing means built into the proposed device makes it possible to adjust the position of the wire portion to be coiled applied to the core at a preset angle and to directly heat this portion by electric current, enabling thereby the use in the coiling process of a wide variety of wire grades as to their diameter and physical properties.

What is claimed is:

l. A device for initial coiling of a filament made of thin wire on a filament core, comprising:

a. a base;

b. a spool with said thin wire;

c. a hollow spindle;

d. said hollow spindle being cantilever-mounted on said base so as to be rotatable;

e. said spool being fixed on a free end of said hollow spindle;

f. a nozzle intended to let said core, pulled through said hollow spindle, pass therethrough;

g. said nozzle being housed in the hollow spindle near its end face;

h. a housing arranged coaxially with said spool and mounted on said base;

i. said housing being adapted to confine the size of a loop formed under the action of centrifugal forces of the wire unrolled from said spool to be coiled;

k. said housing being so mounted on said base as to enable it to move longitudinally relative to said spool;

l. a fixing means ensuring the position of a portion of the wire, fed to the core for coiling, at a predetermined angle;

m. said fixing means being fastened inside the housing on the bottom thereof.

2. A device for initial coiling of a thin wire filament on a filament core as claimed in claim 1, wherein said fixing means is made of conductive material in the form of a ring arranged in a plane normal to and coaxially with the hollow spindle axis and in constant direct contact with said thin wire being coiled forming therewith an electric slide contact connecting said thin wire portion, fed to said core to be coiled thereon, into an electric circuit for heating said portion and controlling its continuity.

3. A device for initial coiling of a thin wire filament on a filament core as claimed in claim 2, wherein said electric circuit includes a relay for controlling breaking of said thin wire, said relay being connected in series with said portion of the thin wire which is fed to the core to be coiled thereon. 

1. A device for initial coiling of a filament made of thin wire on a filament core, comprising: a. a base; b. a spool with said thin wire; c. a hollow spindle; d. said hollow spindle being cantilever-mounted on said base so as to be rotatable; e. said spool being fixed on a free end of said hollow spindle; f. a nozzle intended to let said core, pulled through said hollow spindle, pass therethrough; g. said nozzle being housed in the hollow spindle near its end face; h. a housing arranged coaxially with said spool and mounted on said base; i. said housing being adapted to confine the size of a loop formed under the action of centrifugal forces of the wire unrolled from said spool to be coiled; k. said housing being so mounted on said base as to enable it to move longitudinally relative to said spool; l. a fixing means ensuring the position of a portion of the wire, fed to the core for coiling, at a predetermined angle; m. said fixing means being fastened inside the housing on the bottom thereof.
 2. A device for initial coiling of a thin wire filament on a filament core as claimed in claim 1, wherein said fixing means is made of conductive material in the form of a ring arranged in a plane normal to and coaxially with the hollow spindle axis and in constant direct contact with said thin wire being coiled forming therewith an electric slide contact connecting said thin wire portion, fed to said core to be coiled thereon, into an electric circuit for heating said portion and controlling its continuity.
 3. A device for initial coiling of a thin wire filament on a filament core as claimed in claim 2, wherein said electric circuit includes a relay for controlling breaking of said thin wire, said relay being connected in series with said portion of the thin wire which is fed to the core to be coiled thereon. 